CVE-2021-47602: linux kernel — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: mac80211: track only QoS data frames for admission control For admission control, obviously all of that only works for QoS data frames, otherwise we cannot even access the QoS field in the header. Syzbot reported (see below) an uninitialized value here due to a status of a non-QoS nullfunc packet, which isn't even long enough to contain the QoS header. Fix this to only do anything for QoS data packets.

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-824 CWE-824

Affected Products

Vendor	Product	Versions
linux	linux_kernel	3.19 — 4.19.222
linux	linux_kernel	4.20 — 5.4.168
linux	linux_kernel	5.5 — 5.10.88
linux	linux_kernel	5.11 — 5.15.11
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

Frequently Asked Questions

What is CVE-2021-47602? +

In the Linux kernel, the following vulnerability has been resolved: mac80211: track only QoS data frames for admission control For admission control, obviously all of that only works for QoS data frames, otherwise we cannot even access the QoS field in the header. Syzbot reported (see below) an uninitialized value here due to a status of a non-QoS nullfunc packet, which isn't even long enough to contain the QoS header. Fix this to only do anything for QoS data packets. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2021-47602? +

CVE-2021-47602 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2021-47602? +

CVE-2021-47602 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-47602? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2021-47602